Telephone system



Juhe 17, 193g. J; QSTLINE 1,763,901

TELEPHONE SYSTEM Filed Nov. 13, 1926 3 Sheets-Sheet 1 hm? Jul-Ln E. Drillin June 17, 1930.

J. E. OSTLINE 1,763,901

TELEPHONE SYSTEM I Filed Nov. 13. 1926 3 Sheets-Sheet 2 a I E mm John E. UE'Z'Ziue June 17, 1930. J. E. OSTLINE TELEPHONE SYSTEM 5 Sheets-Sheet 3 Filed Nov. 13, 1926' Inuan or Ju In E. UETIHIIE Patented June 17, 1930 UNITED STATES PATENT OFFICE JOHN ELLIS OSTLINE, OF LIVERPOOL, ENGLAND, ASSIGNO'R, MESNE ASSIGNMENTS,

TO ASSOCIATED TELEPHONE & TELEGRAPH COMPANY, KANSAS CITY, MIS- selector.

SOURI TELEPHONE SYSTEM Application filed November 13, 1926, Serial No. 148,120, and in Great Britain January 16, 1928.

This invention relates to telephone systems and particularly concerns improvements in register controllers for use in such systems. According to the present invention a trunk relay group from which access is had to the register controller is combined with a first numerical switch as in British Patent 233,007, complete accepted May 1, 1925, and is hereinafter referred to as a first code selector.

The first code selector according to the present invention is arranged so that it may be used interchangeably either as an automatic subscribers first code selector or as an operators first code selector there being separate groups of similar switches provided for completing calls from the'two sources. In the former case battery for talking purposes is supplied from'the operators position and in the latter case from the first code When the first code selector is taken into use from a manual position the battery feeding apparatus in the first code selector is disconnected upon response of the called party and the connection is held under the control of the operator over a single conductor which is separate from the speaking circuit. Moreover this first code selector is arranged to have access to twenty trunks from each of its ten levels. In addition to feeding talking battery this improved first code selector controls the connecting up of busy tone currents, number unobtainable tone currents, the metering of completed connections and in the event of a busy line or group of lines being encountered during the setting up of a wanted connection the release of the partly established connection and the transmission of the necessary signalling currents to the calling party (subscriber or operator). In addition this first code selector is arranged to bring about the release o'f the registering apparatus and the connecting up-of signailing currents to the calling line when the number transmitted by the calling party is not correctly recorded on the register switches.

It will be understood that the selector is manufactured without regard as to which of the two services it is to perform, and that the conductors are brought out to. the terminals 1-8, located to the left, so that the switch may function in one manner or the other, depending upon how these terminals are connected through the. usual jack contacts, with which these terminals engage in practice.

In order that the invention may be more fully understood and readily carried into effect, a telephone system according tot-he present invention will now be described with referenceto the accompanying drawin-gsin which Fig. 1 shows the combined operators" or subscribers first code selector switch FCS. Fig. 2 shows a jack ending trunk circuit at an operators position. Fig. 3 shows the A digit register ADS of a register controller and a register control-lei: selector switch RCS.

A detailed description will now be given of the operation of the switch FCS when functioning as a subscribers firs't code ealector and for this purpose we will assume that the terminals 5 and '7, and 6 and 8 are strapped together as shown in Fig. l, and that the conductors extending to terminals 1, 2, 3 and i terminate in "banks of subscribers rotary line switches. When a calling subscriber removes his receiver his rotary line switch will in known manner hunt for an idle trunk and assuming the trunk comprising conductors l, 2, 3 and '4: "is the one taken into use relay L will operate over the following circuit; battery, upper winding of L, incoming negative conductor 1, the calling partys loop, incoming positive conductor 2, lower winding of L, BR, earth. Relay L, upon energizing, performs the fol lowing functions: at L energizes relay BS over the circuit earth, low resistance winding of relay M, L K BB B BS, battery; and at L completes the following circuit for the high impedance relay I and impulse relay A; battery, upper winding of A, N H K strapped terminals 7 and 5,311 winding of relay LK, right hand winding of polarized relay D, strapped terminals 6 and 8, L normally closed contacts eon-v trolled by K, H N lower winding of relay A, 11th stepped cam springs CS to earth. Relays I .and A accordingly operate their armatures 1 and A A respectively. The

polarized relay D however does not operate at this time. Relay BS, upon energizing completes at BS an energizing circuit for the upper winding of relay B and at BS and at BS completes a locking circuit for I itself as follows: earth, BS I, BS BS,

battery. Relay B,'up on-energizin g, earthsthe re'lease'trunk PR at'B over the normally closed contacts controlled by BB and at B completes the following locking circuit for itself: battery, upper winding of B, B

BB K L low' resistance winding of M to earth. flRelay M, however, does not operate at this time owing tothe comparatively high resistance of the upper winding of relayB. Relay A, upon energizing, completes at 'A the following circuit for relay C: battery, winding of C, 0H normal springs .ON, A Dl,-conductor 104, B earth and at A prepares a holding circuit-for the lower winding: of B.v Relay B atB now starts the .register-controller-selector; ROS,

Fig 3, hunting for; an idle A digit switch ADSasffollows: earth, B1104, home positionscontact and test wiper, PVV conductor 103, K C B M to'one side of switching elay K and conductor 102, interrupter contactDM and driving magnet DM to battery. -.As soon as the hunting switch RCS steps off normal, holding earth for switching relay is extended from the homing earth HE over home wiper HW, conductor 100, C to theother side of relay K. Relay K will'be short circuited as long as earth p0 tential is encountered by test wiper PW but when an idle A digit switch is found relay K will energize series with driving magnet DM. Relay C, upon operating, also prepared at C the operating circuit for Vertical magnet V and at C disconnected itself from, theupperwinding of relay A and at contacts C and C? prepared circuits for the shunt field relay E.

1 Upon the register-controller-selector ROS Fig. 3 finding an idle A digit switch ADS, switching relay K Fig. 1 operates and performs the following functions: at K it completes a holding circuit for release'relay B independently of line relay L, at K it completes the following circuitfor relay AA in the A digit switch ADS Fig. 3, earth, low resistance winding of forced release relay M, L K 105, impulse wiper- IW, HH winding of AA to battery. RelayAA energizes in' this circuitbut relay M does not .owing to the comparatively high resistance of the former; Relay AA, upon energizing I completes at AA an energizing circuit-for release relay BB and relay BB earths the re leas etrunk PR at BB and at BB prepares a circuit for connecting the dialing tone to V the calling line. Relay K the relay A and battery.

switch FCS 1 at'K and K switches the'upper and lower windings of the impulse relay A across the negative and positlve wipers VV and +VV of the register- 'controller-selector ROS. Y Dialing tone currentis now fed to the calling party as follows: earth, dial tone transformer DT, 11th step cam springs CSH BB Ill-l wiper W conductor 106, K H N E 7, K

condenser 0' to the incoming-negative speak'-' ing conductor. 1. A branch of this Cli'cult digit switchover conductor 106. Belay K also at K7 completes a holding circuit for itself over conductor 103,- wiper PWV to the earthed releasedtrunk conductor PB and at K disconnects the lower winding of relay M from the vertical magnet. Contacts L of line relay L now serve'as pulsing contacts and hold relay AA in the A digit switch Fig. 3 over the following" circuit: battery,

winding of AA, HH impulsing wiper 1W, l

conductor 105, K L low resistance winding of relay M to earth.

The calling party ing tone may now dial the digits of the Wanted number. Relay L responds to these 1 digits and repeats the first digitto relay AA of the A digit switch ADS and the second and third digitsto the ofiice register magnets of the register-controller taken into use by the A digit switches a result of the dialing of the first digit. Subsequent digitsin the wanted number are repeated by relay L to thevariousnumerical registers associated with the register controller. Relay 1 is'held havingreceived the dialdurin 'the settin of the A di 'it switch b a. b

and ofiice register over a loop circuit in'the switches which extend over the negative wiper WV of switch RC8, conductor 106, K H NflE K BB to one side of relay 1, the other side of relay I being connected to battery vi a K andresistance rwhile. the positive, wiper W 2 of RC8 is connected to earth over conductor 101, K*, H N lower winding of A, US, earth.' As soon as the three code digits of the wanted number have been registered, the register, controller starts sending impulses in known manner over the negative and positive wipers of switch BUS and conductors 106 and101. Relay A of the first code selector'FC/S responds to the'first A series of impulses sent out by the register controller and repeats them at A to the vertical magnet ;V. As soon as the vertical magnet V operates it releases the double dog springs DD and a circuit is completed for both windings of shunt field relay E.

It may be mentioned here that the shunt field relay E is identical with the shunt field relay shown in British Patent No. 170385 and is so constructed that it will only oper ate when both of its windings are energized at the same time. The energizing circuit for relay E is as follows: battery, interrupter springs R of rotary magnet R, double; dog springs DD to the common point of both windings of relay from the other side or the rightharid winding via springs G and B to earth, while the other side of the left hand winding of relay E is connected to earth via springs C and B Relay E, upon operating, completes a lockin circuit for itself at ax-matures E and as follows: battery, interrupter springs R springs DD, both windings of relayE in parallel, armatures E and E, oil normal springs 9N B earth. The first series of impulses is repeated to the yertical magnet V, as fob lows: earth, B D A C V, battery. Upon the first vertical step the oil normal springs ON, 01 1 and 0N operate and relay C is then maintained energized'in parallel with the vertical magnet V during the traismission of remaining impulses in the series. Responsive to this series of impulses, both sets of wipers VV, +VV, 1 3V and +d PiV are raised opposite to l els of bank contacts corresponding to the digit dialed. At the end the of impulses to the vertical magnet V re C will do energize and complete the following circuit for the rotary magnet R: earth, normally closed contacts cont-rolled by C E' winding of rotary magnet R to battery. Rotary magnet It now rotates the shaft carrying the two sets 01" wipers W, N, l? a", and Phi on to the first two trunl: lines in the res ective levels of the Wiper sets and at the same time opening the interrupter springs Rthereby opening the holding circuit oi relay E which deenergizes. The further rotation of the wipers depends on whether or not both trunk lines are busy and supposing this is the case the private wipers PW, Eli of both sets will find earth potential and a circuit will be completed for both windings of relay E which will operate and close the rotary magnet circuit over the same circuit as previously described. Earth on PE will be connected to one winding of relay E over 13 H CS and earth over Pil to the other winding of relay E over H, N and CS This alternate operation of relay E and rotary magnet it will continue as l as both test vh ers PW and Pi l encounter busy contacts. Assuming that one of the wipers PlV P 1 finds a tree trunk, then only one winding of relay E will have a direct circuit while the other winding will have a circuit completed for itself inseries- E does not operate under these conditions and since either relay H or N will operate in series with one of the coils of relay E the speaking conductors will be extended over the wiper-set VV, +W by the operation of relay H and the wiper-set -l i i /V by the operation of relay N. Should the test wipers PW and Fil both engage idle trunks, both relays H and N will energize in series with the windings of relay E but since relays H and N are so arranged that each opens the circuit of the other only one of them' will remain energized and the speaking conductors will be extended only over one set of wipers. Relay E at contacts E also disconnects relay I tlron'i the negative speaking conductor in order to prevent the calling party from hearin the impulses sent out by the register controller.

The subsequent series of impulses sent out by the register controller will be transmitted over the negative and positive wipers of the selected set and at the, end of theimpulse transmission, holding potential will be disconnected froin conductors PE and 103 and relay K will therefore fall back and complete the king circuit between the calling and called parties at K andllh The operation of relay K also releases the A digit switch and register controller in known manner, so that they may be available f r setting up other connections. Upon the release of relay K, the holding circuit for relay B is transferred from K to L and the high impedance relay 1 is connected across the talking conductors in series with the right hand winding of polarized relay I). When the called party answers, relay D operates and at D connects earth to conductor m which serves to operate the calling partys meter. During conversation the switches in the same exchange as the first code selector FCS are maintained energized by guarding potential connected up at B being fed forward over either wiper PW or 13V. The release of the connection is brought about by the calling party replacing his receiver causing relay'L to de-energize and open the circuit of release relay B. Relay B, upon tie-energizing, completes the following circuit torrelease magnet Z: earth, B off normal contacts 0N, release magnet Z to battery. The release of relay B also removes holding potential at B and other operated relays in the first code selector (ls-energize.

Assuming now that a busy condition is encountered during establishment of the connection either by a selector or connector. In either case battery and earth alternately will be connected to the negative speaking conductor whereupon relay 1 will de-energize and re-energize. Since the battery period will cause relay I to open the circuit of relay BS for a period long enough to :allow it to release the following circuit will be completed for relay BR upon the re-energization of relay 1: battery, upper winding of BR, normally closed springs controlled by BB BS I, BS 104:, B earth. Relay BR, upon energizing, will release the partly established connection in the same manner as .ifthe callingparty had replaced his receiver in the ordinary way,the only difference being that relay L is still energized and now 7 controls relay BR which guards the calling line at BB It will be seen that relay BB upon energizing opens at BB the energizing circuit for release relay B and that relay BR connects at BB the combined busy tone and busy flash signalling conductor BTF, to the calling line through the lower winding of relay L. Responsive to this operation the calling party (subscriber or operator) will receive the usual busy signal i. e. tone to a calling automatic subscriber and a flashing signal to an operator. During the period that battery is connected to the lower winding of relay L as a result of a busy line being encountered, relay BB is held energized over its upper winding and the holding conductor it. It should be noted alsothat the release of the partly established connection holding period of the switch where the busy condition originates and therefore no earth holding is required. In the case of a busy tone arising-at the A digit switch, relay I will be interrupted as before and bring about is arranged to take place durin the nonthe above condition as well as the release of the A digit switch.

In the case of a time pulse cut-off either at the A digit switchlor in the register controller, relay M in the first code selector will be operated over its low resistance winding as follows: battery connected up as a result of the operation of the time pulse relay to conductor 105, K L, low resistance, winding of relay M to earth. Relay M operates under these conditions and completes the following circuit for relay BR: battery, upper winding of BR, normally closed contacts controlled by BB v1 C B earth. Relay BR upon operating will release any partly operated equipment by bringing about the release of release relay B. With rela s M and BB in onerated )ositions, a number unobtainable tone and flashing signal current superimposed on conductor NUT is connected via contacts M, BR and the lower windlng of relay L to the incoming positive speaking conductor in order to notify the calling subscriber or operator that the wanted number is unobtainable.

In the case where the calling party removes his receiver but does not dial in any digits, the A digit switch will be released by" the operation of the time pulse relay TP causing battery to be connected to conductor 105 as follows: battery, T T1,

G, TF4, EH2, 1W, conductor 105, K2, L,

low resistance of M to earth. Since this FCS is adapted to be taken into use by an operator the connections to the terminals 18, Figs. 1 and 2, are as indicated in Fig. 2 instead of as indicated in Fig. 1.

When the operator inserts a-plug in the jack associated with the trunk leading to the first code switch FCS the sleeve relay S operates from earth on the sleeve of the plug and prepares at S a holding circuit for re lay LR. Relay L ,ingthe switch FCS energizes over conductors l and2 inthe following circuit: battery, upper w nding of relay L, conductor- 1, LE tipof jack, operators. 1 loop, ring of gack, LE conductor 2,}lower winding of L, BB earth. Belay L operates as before and completes acircuit at'L for relay BS and the latter relay completes at BS a circuit for relay B. Relay B, (upon operating, earths the release trunk PR at armature B This earth extends over conductor 3 and causes the supervisory lamp associated with the jackof this trunk to glow. The operator now dials the digits in the wanted number which are recorded in the register controller. taken into use by. the

first code selector FCS. The register controller sends out the necessary digits to establish connection with the wanted party and when the wanted party answers'the polarized relay D in the first code selector 7 will operate and connect earth'to the meter-.

ing conductor'm as follows: earth, B D metering conductor m. The earth potential on the metering conductor m now extends over conductor 4, normally closed contacts controlled by armature LR, winding of relay board energizes in series with the upper winding of relay L of switch F CS and'at' Ll? completes a locking circuit for'itself and at LE and LE disconnects the condensers c and c, the line winding'of polarized D and the high impedance-relay I from the LR, conductor 1, upper winding ofrelay L to battery. Relay LR in the manual speaking conductors of the first code switch 7 FCS and extends the tip and ring conductors of the jack over the conductors 7 and 8 to the speaking conductors of the first code switch. Relay L remains energized in series with relay LB in order to complete the talking circuit at L and to control the release of the'connection at L The removal of the polarized relay D from the speaking conduct-crs will cause it to dcenergize and remove earth from conductor 4-. hen the operator remores the plug from the acl; the sleeve relay S will deenergize and at S open a holding circuit for relays LR and L.

W ha-t I claim as new and desire to secure by Letters Patent is 1. In a telephone system employing registering apparatus and which access to such apparatus is had from a trunk relay group, circuit connections in said trunk relay group for supplying talking current to one of the subscribers involved when the call is set up from an automatic line, and means effective in case the call is coming from a manual switchboard for altering the connections in the trunk relay group upon the response of the called subscriber so that talking current is supplied to the called line from the switchboard through such relay group.

2. In a telephone system employing registering apparatus and in which access is had to such apparatus from a trunk relay group, circuit connections in such relay group arranged to secure the proper functioning when the call extended thereto is from an automatic subscribers line, and circuit changing means operated automatically upon the response of the called subscriber for suitably altering the circuit connections in case the call is I coming from a manual switchboard. V

3. In a telephone system employing registering apparatus and in which access is had to such apparatus from a battery-feeding relay group, means for automatically disconnecting the battery feeding apparatus of the relay group upon the response of the called subscriber in case the call originates at a manual switchboard.

4. In a telephone system employing registering apparatus and in which access is had to such apparatus from a trunk relay group, said relay group being arranged so that it is readily adaptable for use either for completing calls originated on a calling subscriber lines and for completing calls originating at a manual switchboard, a metering conductor at said relay group together with means for operating a meter thereover when the called subscriber responds in case the call is from an automatic subscriber line, and circuit-changing apparatus operated over said metering conductor instead oi said meter in case the trunk relay group is unctioning in connection with a manual switchboard instead of in connection with automatic lines.

5. In a telephone system employing registering apparatus and in which access is had to such apparatus troma trunk relay group, an impulse responding relay in? said relay group arranged to be controlled over a loop circuit during the setting up of a connection, and means effective upon the response of the called subscriber for disconnecting the impulse responding relay from the talking circuit and for holding up the connection by holding it-operated in an independent circuit. r

6. In a telephone a supervisory relay in the trunk relay group havinga low resistance winding, and a circuit controlled by the impulse responds ing relay for repeating impulses to the registering apparatus through such low resistance winding. f

7. In a telephone'system employing register switches and in which access is'had to the registerswitches from a trunk relay group, a relay in saidltrunk relay group ar ranged to be controlled over a partlyestab lished connection, and means responsive to a prolongeddeenergization and a reenergizaion of said relay'for releasing such partly established connection and for giving the calling party a busysignal.

8. In a telephone system as claimedin claim 7, means effective in case the number. transmitted by the calling party is {not correctly recorded on the register 7 switches for releasing the register switches and for connecting up a signaling current to the calling line.

9. In a telephone system, an automatic switch arranged to extend an incoming trunk line of either of two diflerenttypes, the types of said trunk line being such that they must be differently connected to said switch and terminal facilities so arranged that the switch may be used interchangeably to extend connections from an incoming trunk line of either type.

10. In a telephone system, a trunk line of one type having a given number of conducsystem claimed inclaim tors, a trunk line of another type having a larger. number of conductors, an automatic switch arrangedwith the proper nmnber of incoming conductors to extend a connection from the last named trunk, but capable of use with said first named trunk, and termi nal facilities so arranged that when the switch is used in connection with the trunk line having the smaller number of conductors the excess conductors incoming to the switch are looped together.

11'. In a telephone system, a, trunk line having a plurality of conductors, a trunk line having a larger plurality of conductors, an automatic switch arranged to extend a connection from either trunk line and having conductors brought out to terminals and corresponding respectively to the conductors of said trunk line having the larger plurality of conductors, and terminal facilities such that, when a switch is used to extend a the trunk line having the smaller number of conductors,- each' 0f the conductors broughtout to terminals and which does'not correspond to a conductor of the trunk line last named is connected to another of the said conductors of the switch a 12. In a telephone system, an automatic switch having talking conductors therein,

each vof. said talking conductors being opened with the Open ends brought out to terminals, and terminal facilities such that the open ends of the talking conductors a may be closed locally in case'the switch is used as the terminus of an incoming'trunk of one type andmay be connected to incoming trunk conductors in case' theswitch is used as the terminus of an incoming trunk of another type. I 3

13.'In a telephone system, a trunk line having 'aplurality of conductors, a trunk line having a different number of conductors, an automatic switch arranged to serve as the terminus for. either trunk line interchangeably, and -means including terminal 7 Wiring for completing local circuits overrun- October 1926.

- JOHN ELLIS OSTLINE. 7 

